1. Field of the Invention
The present invention relates to a test apparatus and, more particularly, to a test apparatus for verifying the position of electrical contacts within a sliding SIM mechanism.
2. Description of the Related Art
Some radio telephone systems, such as digital cellular phone systems, employ IC cards, known as SIM (subscriber interface module) cards, which are inserted into a radio telephone for providing subscriber identification, billing information and other information concerning the operation of the radio telephone. For example, the SIM card might record the subscriber telephone number, a personal identification number, as well as call charge information or a telephone number index.
To transfer information between the SIM card and the radio telephone, a SIM card reader and connector is provided in the body of the radio telephone. The SIM card reader generally includes two rows of either four or three SIM card contacts which correspond to the contacts on the SIM card. When the SIM card is slid into the body of the cellular telephone, the SIM card's contacts mate with the SIM card reader contacts. In particular, typical SIM cards are slid into the SIM card slot until the leading edge of the SIM card hits a hard stop. A home switch is activated at or just before the point of the stop. Typically, the electronics are activated simultaneously with activation of the home switch. Thus, when the home switch is activated, the contacts in the SIM card reader must be guaranteed to be mating with the contact on the SIM card itself. The electrical interface can lock up if a proper connection is not assured. In addition, damage to the cards can result. Such lock ups and damage can result in dissatisfied customers and high rates of returns and higher costs.
Accordingly, there is a need for an improved method for insuring that the contacts on the SIM card reader are properly configured with respect to the SIM card contacts on the SIM card itself. More particularly, there is a need for accurately measuring the position of contacts within the SIM card reader relative to the home switch during the development process.